Update on novel synthetic approaches towards the construction of carbazole nuclei: a review

RSC Advances, Journal Year: 2024, Volume and Issue: 14(5), P. 2929 - 2946

Published: Jan. 1, 2024

The carbazole scaffold is a significant entity in organic compounds due to its variety of biological and synthetic applications. Traditionally, skeletons have been synthesized either via the Grabe-Ullman method, Clemo-Perkin method or Tauber method. With passage time, these methods modified explored accomplish synthesis target compounds. These include hydroarylations, C-H activations, annulations cyclization reactions mediated by catalysts construct carbazole-based This brief review article intends provide recent updates on important methodological developments reported for nuclei covering 2019-2023.

Language: Английский

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Synthesis of Highly Fluorescent Thiazole Fused Benzo[a] Carbazoles by Sunlight Driven Photocyclization of Indolylthiazoles

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 19, 2024

Abstract Herein we report for the first time a sunlight‐driven, irreversible photocyclization reaction of indole‐linked trisubstituted thiazoles, synthesis highly fluorescent thiazole‐fused benzo[ ]carbazoles using mixture solvents (CH 3 CN: DMSO; : 1). Ring opening indole moiety was observed in case thiazole derivatives having 2‐methyl substituents. Under similar conditions, thiazoles cyclic 1,3‐dicarbonyls place also worked. This provides products two medicinally important moieties and benzocarbazoles. We have studied photophysical properties all found that most synthesized very good fluorescence quantum yields.

Language: Английский

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CuCl/Ionic Liquid Catalyzed Cascade Transformation of CO2 and Alkyne-1,2-Diols: Synthesis of Keto-Functionalized Cyclic Carbonates

Catalysts, Journal Year: 2025, Volume and Issue: 15(3), P. 279 - 279

Published: March 17, 2025

The cyclization of propargyl alcohols with CO2 represents a highly significant method for the utilization CO2. resulting cyclic carbonates possesses high chemical value and hold great potential applications in battery electrolytes, polymer precursors, pharmaceutical intermediates. However, most existing reports on this have been limited to simple alcohol substrates that are substituted inert alkyl, cycloalkyl, phenyl groups. For functionalized alcohols, such as alkyne-1,2-diols, only single report has documented thus far. In study, we developed an innovative catalytic system comprising cost-effective copper salts environmentally friendly ionic liquids (CuCl/1-ethyl-3-methylimidazolium acetate) alkyne-1,2-diols Compared previously reported AgF/bulky monophosphine ligand (BrettPhos) system, our is free traditional volatile solvents, phosphine ligands, additives. Notably, first Cu(I)-catalyzed cyclization, offering advantages terms cost-effectiveness reduced toxicity compared silver salts. Moreover, use ensures considerable recyclability, further enhancing sustainability practicality approach.

Language: Английский

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Catalyst-Controlled C–H Allylation and Annulation of 2-Aryl Quinazolinones with 2-Methylidene Cyclic Carbonate

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(18), P. 13315 - 13326

Published: Sept. 5, 2023

The site-selective modification of quinazolinone as a privileged bicyclic N-heterocycle is an attractive topic in medicinal chemistry and material science. We herein report the ruthenium(II)-catalyzed C-H allylation 2-aryl quinazolinones with 2-methylidene cyclic carbonate. In addition, tandem annulation are achieved under rhodium(III) catalysis, resulting formation tetracyclic including tertiary carbon center. Post-transformations synthesized products demonstrate potential developed methodology. A series mechanistic investigations were also performed.

Language: Английский

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Ru(II)‐Catalyzed ortho C—H Allylation of N‐Aryl‐7‐azaindoles with 2‐Methylidene Cyclic Carbonate

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 42(9), P. 985 - 989

Published: Dec. 26, 2023

Comprehensive Summary A Ru(II)‐catalyzed ortho allylation reaction of N ‐aryl‐7‐azaindole with readily available 2‐methylidene cyclic carbonate has been developed. This is an effective pathway for synthesizing 7‐azaindole derivatives a wide scope substrates and high yields. In addition, the method can be extended to other heterocyclic compounds several carbonates, highlighting practicality this strategy synthesis.

Language: Английский

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Dual Reactivity Mode of Vinyl Ethylene Carbonates with Anilines: A Catalyst-Controlled Chemodivergent Entry to N-Heterocycles and the Observation of Unusual Competing Pathways

Published: June 25, 2024

A unique catalyst-controlled chemodivergent strategy to access 2-vinyl indolines and indole-2-acetates by overcoming the usual allylic reactivity of vinyl ethylene carbonates (VECs) via a tandem C-H/C-O bond activation sequence is disclosed herein. This methodology provides useful molecular scaffolds following two distinct pathways in highly step- atom-economical manner. The pathway features challenging beta-hydroxide elimination Rh-catalyzed transformation, we have observed unusual competing such as an oxidative insertion MeOH into Rh(III) give putative Rh(V)-H intermediate. Mechanistic insights unveil new mode open avenue for divergent catalysis. Post synthetic modification annulated products add additional advantage methodology.

Language: Английский

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Synthesis of Quinoline–Indole Hybrids through Cu(II)-Catalyzed Amination and Annulation between N-Oxides and o-Alkynylanilines

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

The synthesis of (iso)quinoline-indole hybrids by reacting (iso)quinoline N-oxides with o-alkynylanilines in the presence a combination copper(II) catalyst and bidentate 2,2′-bipyridine ligand is described. utility this method was demonstrated through site-selective functionalization synthesized products. A plausible reaction pathway for amination followed annulative indole formation elucidated series mechanistic investigations.

Language: Английский

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FeCl₃-catalyzed AB₂ three-component [3 + 3] annulation: an efficient access to functionalized indolo[3,2-b]carbazoles

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(23), P. 5978 - 5985

Published: Jan. 1, 2023

An FeCl 3 -catalyzed AB 2 three-component reaction of indole-2-carbaldehydes and 5-aminopyrazoles was established for the synthesis indolo[3,2- b ]carbazoles.

Language: Английский

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Construction of Nitrogen Spirocycles in a Tandem Co(III)‐catalyzed C−H Activation/Dipolar Cycloaddition Reaction

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(23), P. 4241 - 4247

Published: Oct. 30, 2023

Abstract Complex spirocyclic isoindolines and pyrrolidines are formed in a tandem process involving Co(III)‐catalyzed dienylation of cyclic C‐aryl nitrones with 2,3‐butadien‐1‐ol carbonates, followed by intramolecular 1,3‐dipolar cycloaddition. The nitrone moiety serves both as directing group for the C(aryl)−H activation dipole cycloaddition step. High regioselectivity fused vs. bridged product can be obtained adjusting reaction temperature. Reactions substituted allenic substrates provide heterocycles additional stereocenters usually complete diastereoselectivity. products were readily transformed further into other complex nitrogen‐containing systems.

Language: Английский

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Tandem annulation and dipolar cycloaddition of azomethine imines in catalytic C(sp²)–H functionalization

Bulletin of the Korean Chemical Society, Journal Year: 2023, Volume and Issue: 45(2), P. 131 - 144

Published: Dec. 12, 2023

Abstract The synthesis and functionalization of privileged nitrogen heterocycles has emerged as a central topic in drug discovery material science. In this context, the tandem C–H intramolecular annulation received prodigious attention, it is able to expedite construction heteroaromatic frameworks beyond conventional functionalization. general, significant effort been made develop [3 + 2] dipolar cycloaddition azomethine imines with π‐unsaturated compounds. Moreover, 3], [4 2 2], [5 3] reactions various dipolarophiles have demonstrated. To date, however, combination catalytic cyclization using both directing groups units less explored. This review focuses on recent progress toward azomethines range coupling partners.

Language: Английский

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